A Motor-Driven Power Steering System (MDPS) supplements the steering force of a steering wheel using a motor and provides the advantage of increased fuel efficiency and simple control because it does not use the power from an engine, unlike the existing hydraulic power steering system.
The MDPS supplements the steering torque applied by a driver and provides steering force at all times while the vehicle is being driven. That is, a motor is controlled by an MDPS controller and power from the motor provides supplemental steering force for a driver, thereby reducing the fatigue of the driver.
Meanwhile, when a vehicle is driven straight with the steering angle of the steering wheel maintained at an on-center position, the vehicle is theoretically driven straight without tilting in any direction, but it may tilt in any one direction while it is driven due to a change in alignment, the slope of a road, or lateral wind.
In particular, when a vehicle rapidly changes speed such, as rapid acceleration, while it is driven straight, the vehicle is tilted due to slippage of the tires. However, it takes a long time and a lot of expense to analyze and fundamentally solve this problem, so there is a need for an additional solution.
The description provided above as a related art of the present invention is only for helping understanding the background of the present invention and should not be construed as being included in the related art known by those skilled in the art.